A new study on flies has suggested that past male mates might have an impact on the future offspring of females in situations where the actual male parent is another individual entirely. The researchers believe that the eggs of the females might have absorbed some of the seminal fluids of their ex-partners that persist in their systems such that the growth of their offspring is affected.

Introducing telegony: Offspring resembles the ex of Mama Fly

We generally cringe when reminded of ‘exes’, be they past boyfriends/ girlfriends or ex-spouses. Getting over surely does get better when one gives time to time. Well, female flies might not be having the privilege of getting rid of all reminders of their past mates. A new study has shown that after the ‘break-up’, they might still be conserving the DNA of the male fly, such that the female’s offspring resembles the latter – a theory known as telegony.

Telegony: Disproved theory in the limelight again

Telegony as a concept budded off the mind of Aristotle, the famous Greek philosopher. It had gained quite acclaim during that time, and remained a science up until the 1900s when modern genetics revolutionised our perception. However, this new study implies that telegony might be having rings of truth to it in the world of flies.

The experiment

The study has shown that the progeny of the female fly can bear close resemblance to its mother’s past sexual partner even though the latter did not actively contribute its DNA for its making. How demeaning to the actual daddy fly! He gives away his very sperm, but still, his progeny takes some characteristics from his ‘rival’.

For the purpose of the experiments, female flies were made to mate with male flies twice: once, with either large or small males while the female were immature, and for the second time, having reached maturity, they mated again with males of different sizes. The offspring of the second batch were studied. That was when aspects of telegony were found.

Discussing the results: Male seminal fluids absorbed in females’ eggs

“We found that even though the second male sired the offspring, offspring size was determined by what the mother’s previous mating partner ate as a maggot,” explained Dr. Angela Crean, lead author of the study. “Our new findings take this to a whole new level — showing a male can also transmit some of his acquired features to offspring sired by other males.”

The reason as to the phenomenon is not yet clarified. The scientists have speculated that this may be due to remnants of the seminal fluid of the males of the first batch having persisted in the females’ bodies. Molecules of the seminal fluid might have been absorbed into the immature eggs of the females, and have thus impacted on the progeny of the latter.

What about us, humans?

Could this be superimposed on us, humans? Could genetics trick us into producing such results too? Commenting on relating the results to us Dr Crean said: “There is no evidence of such effects in humans, but there has not been any research on this possibility in humans. There is a potential for such effects in mammals. For example, there is a lot of foetal DNA in maternal blood during pregnancy, and this could potentially play a role in such effects. There is also evidence in mammals that seminal fluid affects offspring development, so semen from one male could potentially influence the development of eggs fertilized by another male (which is what we think is happening in flies).”

Performing experiments on humans to prove or disprove telegony among us would be unethical though. Hopefully, scientists will find other ways to determine whether telegony happens among us.